A method for group key distribution with forward security

Abstract

The invention discloses a group key distribution method with forward security. In order to realize secure communication between users in the group, it is necessary to use the group key to encrypt and decrypt the communication content. Therefore, before the secure communication within the group starts, the group key used for this communication needs to be safely distributed to the users in the group who need to communicate. The key problem solved by the invention is how to carry out group key distribution with forward security without a trusted third party. The present invention utilizes the symmetric binary polynomial to negotiate a symmetric key between each pair of users in the group, and uses the symmetric key to realize the safe distribution of the group key. At the same time, the present invention maintains a communication record table for each user, and updates the symmetric key between users for securely distributing the group key of the next round of intra-group communication according to the record table, thereby achieving forward security group key distribution.

Description

technical field [0001] The invention belongs to the technical field of information security, relates to a method for distributing a group key, in particular to a method for distributing a group key with forward security. Background technique [0002] Intra-group secure communication has a wide range of applications. For example, in an enterprise, the chairman convenes the leaders of various departments to conduct secure voice conferences or video conferences through open channels, or the technical department conducts secure technical solution discussions through open channels, etc., all of which require secure intra-group communication. How to achieve safe intra-group communication? A common practice is to safely distribute a group key to users in the group who need to communicate, and use this group key to encrypt and decrypt the communication information of these users. There are usually two types of methods for safely distributing group keys: one is that there is a "use...

AI Technical Summary

Problems solved by technology

However, this method requires each user to maintain n(n-1) / 2 "user pair keys" (assuming there are n users in the group), which will bring relatively large storage overhead, and is not suitable for grouping through mobile devices. Users who communicate within the group; and the "user-to-key" between users is fixed, which will bring some security problems. The "user pair key", then the adversary can obtain the communication information of the intra-group communication they participated in before through the "user pair key"

Images